Synthesis and characterization of spent alumina catalyst and grinding sludge reinforced aluminium-based composite material

In this investigation, an attempt has been made to use the waste material in the fabrication of aluminium-based composite material. Waste spent alumina catalyst (SAC) generated from oil refinery industries has been considered as primary reinforcement particle. Waste grinding sludge (GS) produced from iron forging industry was used as secondary reinforcement material in the preparation of composite. Further, chromium (Cr) has been added to SAC and grinding sludge (GS) reinforced aluminium-based composite material to prevent grain growth as well as to control the grain structure of composite material. Experimental results concluded that by adding 4.5% of GS and SAC with 1.5% Cr in aluminium alloy, mechanical properties such as hardness, compressive strength and tensile strength were significantly improved. Hardness compressive strength and tensile strength was increased by 40.06%, 7.24% and 18.86%, respectively, with respect to the aluminium alloy. However, the reduction in toughness was observed. SEM results depicted uniform distribution of SAC and GS particles in Al/4.5% SAC/4.5% GS/1.5% Cr composite. Thermal expansion behaviour and corrosion weight loss of composite have been also investigated to observe the influence of reinforcement in the aluminium alloy.